We buy things we don't need with money we don't have to impress people we don't like.

The Total Money Makeover Classic Edition - A Proven Plan for Financial Fitness (2004).

The idea is expressed twice in the same book: People were running around buying things they couldn't afford with money they didn't have to impress people they didn't even like, and they were doing it in record numbers.

But it is important to notice that he was not the first one to come up with this concept:

See: Advertising has these people...

See also: Using money you haven't...